//#include <StdAfx.h>
#include "md5.h"
#include <stdio.h>

namespace crypto
{

#define GET_UINT32(n, b, i)                                     \
{                                                               \
    (n) = (__uint32) ((__uint8 *) b)[(i)]                           \
    | (((__uint32) ((__uint8 *) b)[(i)+1]) <<  8)                   \
    | (((__uint32) ((__uint8 *) b)[(i)+2]) << 16)                   \
    | (((__uint32) ((__uint8 *) b)[(i)+3]) << 24);                  \
}

#define PUT_UINT32(n, b, i)                                     \
{                                                               \
    (((__uint8 *) b)[(i)]  ) = (__uint8) (((n)      ) & 0xFF);      \
    (((__uint8 *) b)[(i)+1]) = (__uint8) (((n) >>  8) & 0xFF);      \
    (((__uint8 *) b)[(i)+2]) = (__uint8) (((n) >> 16) & 0xFF);      \
    (((__uint8 *) b)[(i)+3]) = (__uint8) (((n) >> 24) & 0xFF);      \
}

void MD5::md5_starts(struct md5_context *ctx )
{
    ctx->total[0] = 0;
    ctx->total[1] = 0;
    ctx->state[0] = 0x67452301;
    ctx->state[1] = 0xEFCDAB89;
    ctx->state[2] = 0x98BADCFE;
    ctx->state[3] = 0x10325476;
}

void MD5::md5_process(struct md5_context *ctx, __uint8 data[64])
{
    __uint32 A, B, C, D, X[16];

    GET_UINT32( X[0],  data,  0 );
    GET_UINT32( X[1],  data,  4 );
    GET_UINT32( X[2],  data,  8 );
    GET_UINT32( X[3],  data, 12 );
    GET_UINT32( X[4],  data, 16 );
    GET_UINT32( X[5],  data, 20 );
    GET_UINT32( X[6],  data, 24 );
    GET_UINT32( X[7],  data, 28 );
    GET_UINT32( X[8],  data, 32 );
    GET_UINT32( X[9],  data, 36 );
    GET_UINT32( X[10], data, 40 );
    GET_UINT32( X[11], data, 44 );
    GET_UINT32( X[12], data, 48 );
    GET_UINT32( X[13], data, 52 );
    GET_UINT32( X[14], data, 56 );
    GET_UINT32( X[15], data, 60 );

#define S(x, n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))

#define P(a,b,c,d,k,s,t)                                    \
    {                                                       \
    a += F(b,c,d) + X[k] + t; a = S(a,s) + b;           \
    }

    A = ctx->state[0];
    B = ctx->state[1];
    C = ctx->state[2];
    D = ctx->state[3];

#define F(x,y,z) (z ^ (x & (y ^ z)))

    P( A, B, C, D,  0,  7, 0xD76AA478 );
    P( D, A, B, C,  1, 12, 0xE8C7B756 );
    P( C, D, A, B,  2, 17, 0x242070DB );
    P( B, C, D, A,  3, 22, 0xC1BDCEEE );
    P( A, B, C, D,  4,  7, 0xF57C0FAF );
    P( D, A, B, C,  5, 12, 0x4787C62A );
    P( C, D, A, B,  6, 17, 0xA8304613 );
    P( B, C, D, A,  7, 22, 0xFD469501 );
    P( A, B, C, D,  8,  7, 0x698098D8 );
    P( D, A, B, C,  9, 12, 0x8B44F7AF );
    P( C, D, A, B, 10, 17, 0xFFFF5BB1 );
    P( B, C, D, A, 11, 22, 0x895CD7BE );
    P( A, B, C, D, 12,  7, 0x6B901122 );
    P( D, A, B, C, 13, 12, 0xFD987193 );
    P( C, D, A, B, 14, 17, 0xA679438E );
    P( B, C, D, A, 15, 22, 0x49B40821 );

#undef F

#define F(x,y,z) (y ^ (z & (x ^ y)))

    P( A, B, C, D,  1,  5, 0xF61E2562 );
    P( D, A, B, C,  6,  9, 0xC040B340 );
    P( C, D, A, B, 11, 14, 0x265E5A51 );
    P( B, C, D, A,  0, 20, 0xE9B6C7AA );
    P( A, B, C, D,  5,  5, 0xD62F105D );
    P( D, A, B, C, 10,  9, 0x02441453 );
    P( C, D, A, B, 15, 14, 0xD8A1E681 );
    P( B, C, D, A,  4, 20, 0xE7D3FBC8 );
    P( A, B, C, D,  9,  5, 0x21E1CDE6 );
    P( D, A, B, C, 14,  9, 0xC33707D6 );
    P( C, D, A, B,  3, 14, 0xF4D50D87 );
    P( B, C, D, A,  8, 20, 0x455A14ED );
    P( A, B, C, D, 13,  5, 0xA9E3E905 );
    P( D, A, B, C,  2,  9, 0xFCEFA3F8 );
    P( C, D, A, B,  7, 14, 0x676F02D9 );
    P( B, C, D, A, 12, 20, 0x8D2A4C8A );

#undef F

#define F(x,y,z) (x ^ y ^ z)

    P( A, B, C, D,  5,  4, 0xFFFA3942 );
    P( D, A, B, C,  8, 11, 0x8771F681 );
    P( C, D, A, B, 11, 16, 0x6D9D6122 );
    P( B, C, D, A, 14, 23, 0xFDE5380C );
    P( A, B, C, D,  1,  4, 0xA4BEEA44 );
    P( D, A, B, C,  4, 11, 0x4BDECFA9 );
    P( C, D, A, B,  7, 16, 0xF6BB4B60 );
    P( B, C, D, A, 10, 23, 0xBEBFBC70 );
    P( A, B, C, D, 13,  4, 0x289B7EC6 );
    P( D, A, B, C,  0, 11, 0xEAA127FA );
    P( C, D, A, B,  3, 16, 0xD4EF3085 );
    P( B, C, D, A,  6, 23, 0x04881D05 );
    P( A, B, C, D,  9,  4, 0xD9D4D039 );
    P( D, A, B, C, 12, 11, 0xE6DB99E5 );
    P( C, D, A, B, 15, 16, 0x1FA27CF8 );
    P( B, C, D, A,  2, 23, 0xC4AC5665 );

#undef F

#define F(x,y,z) (y ^ (x | ~z))

    P( A, B, C, D,  0,  6, 0xF4292244 );
    P( D, A, B, C,  7, 10, 0x432AFF97 );
    P( C, D, A, B, 14, 15, 0xAB9423A7 );
    P( B, C, D, A,  5, 21, 0xFC93A039 );
    P( A, B, C, D, 12,  6, 0x655B59C3 );
    P( D, A, B, C,  3, 10, 0x8F0CCC92 );
    P( C, D, A, B, 10, 15, 0xFFEFF47D );
    P( B, C, D, A,  1, 21, 0x85845DD1 );
    P( A, B, C, D,  8,  6, 0x6FA87E4F );
    P( D, A, B, C, 15, 10, 0xFE2CE6E0 );
    P( C, D, A, B,  6, 15, 0xA3014314 );
    P( B, C, D, A, 13, 21, 0x4E0811A1 );
    P( A, B, C, D,  4,  6, 0xF7537E82 );
    P( D, A, B, C, 11, 10, 0xBD3AF235 );
    P( C, D, A, B,  2, 15, 0x2AD7D2BB );
    P( B, C, D, A,  9, 21, 0xEB86D391 );

#undef F

    ctx->state[0] += A;
    ctx->state[1] += B;
    ctx->state[2] += C;
    ctx->state[3] += D;
}

void MD5::md5_update(struct md5_context* ctx, __uint8* input, size_t length)
{
    __uint32 left, fill;

    if (!length ) return;

    left = ( ctx->total[0] >> 3 ) & 0x3F;
    fill = 64 - left;

    ctx->total[0] += (unsigned int)(length << 3);
    ctx->total[1] += (unsigned int)(length >> 29);

    ctx->total[0] &= 0xFFFFFFFF;
    ctx->total[1] += ctx->total[0] < length << 3;

    if (left && length >= fill)
    {
        memcpy((void *) (ctx->buffer + left), (void*)input, fill );
        md5_process(ctx, ctx->buffer);
        length -= fill;
        input  += fill;
        left = 0;
    }

    while (length >= 64)
    {
        md5_process(ctx, input);
        length -= 64;
        input  += 64;
    }

    if (length)
    {
        memcpy((void *)(ctx->buffer + left), (void *)input, length);
    }
}

static __uint8 md5_padding[64] =
{
    0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};

void MD5::md5_finish(struct md5_context* ctx, __uint8 digest[16])
{
    __uint32 last, padn;
    __uint8 msglen[8];

    PUT_UINT32( ctx->total[0], msglen, 0 );
    PUT_UINT32( ctx->total[1], msglen, 4 );

    last = ( ctx->total[0] >> 3 ) & 0x3F;
    padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last );

    md5_update( ctx, md5_padding, padn );
    md5_update( ctx, msglen, 8 );

    PUT_UINT32( ctx->state[0], digest,  0 );
    PUT_UINT32( ctx->state[1], digest,  4 );
    PUT_UINT32( ctx->state[2], digest,  8 );
    PUT_UINT32( ctx->state[3], digest, 12 );
}

string MD5::GenerateMD5(unsigned char* buffer, size_t bufferlen)
{
    struct md5_context context;
    md5_starts (&context);
    md5_update (&context, buffer, bufferlen);
    md5_finish (&context,(unsigned char*)m_data);

    return this->ToString();
}

MD5::MD5()
{
    for(int i = 0;i < 4; i++)
        m_data[i] = 0;
}

MD5::MD5(unsigned int* md5src)
{
    memcpy(m_data, md5src, 16);
}

int _httoi(const char* value)
{
    struct CHexMap
    {
        char chr;
        int value;
    };

    const int HexMapL = 16;
    CHexMap HexMap[HexMapL] =
    {
        {'0', 0}, {'1', 1},
        {'2', 2}, {'3', 3},
        {'4', 4}, {'5', 5},
        {'6', 6}, {'7', 7},
        {'8', 8}, {'9', 9},
        {'a', 10}, {'b', 11},
        {'c', 12}, {'d', 13},
        {'e', 14}, {'f', 15}
    };

#ifdef _MSC_VER
    char* mstr = _strdup(value);
#else
    char* mstr = strdup(value);
#endif
    char* s = mstr;
    int result = 0;
    if (*s == '0' && *(s + 1) == 'X') s += 2;
    bool firsttime = true;
    while (*s != '\0')
    {
        bool found = false;
        for (int i = 0; i < HexMapL; i++)
        {
            if (*s == HexMap[i].chr)
            {
                if (!firsttime) result <<= 4;
                result |= HexMap[i].value;
                found = true;
                break;
            }
        }
        if (!found) break;
        s++;
        firsttime = false;
    }

    free(mstr);

    return result;
}

MD5::MD5(const char* md5src)
{
    if (strcmp(md5src, "") == 0)
    {
        for(int i = 0;i < 4; i++)
            m_data[i] = 0;

        return;
    }

    for (int j = 0; j < 16; j++ )
    {
        char buf[10];
#ifdef __linux__
        strncpy(buf, md5src, 2);
#else
        strncpy_s(buf, 10, md5src, 2);
#endif
        md5src += 2;
        ((unsigned char*)m_data)[j] = _httoi(buf);
    }
}

MD5 MD5::operator + (MD5 adder)
{
    unsigned int m_newdata[4];

    for(int i = 0; i < 4; i++)
        m_newdata[i] = m_data[i] ^ (adder.m_data[i]);

    return MD5(m_newdata);
}

bool MD5::operator == (MD5 cmper)
{
    return (memcmp(cmper.m_data, m_data, 16) == 0);
}

string MD5::ToString()
{
    char output[33];

    for(int j = 0; j < 16; j++ )
    {
#ifdef __linux__
        sprintf(output + j * 2, "%02x", ((unsigned char *)m_data)[j]);
#else
        sprintf_s(output + j * 2, 2, "%02x", ((unsigned char *)m_data)[j]);
#endif
    }

    return string(output);
}

}
